TRANSPORTATION; The Taconic Parkway: A Road in Transition

FROM the hills, farms and forests of the mid-Hudson Valley, Franklin Delano Roosevelt's wisp of road drops patiently down to Valhalla. John Porcella travels it daily, with its layers of scenery, its wild turkeys, the cars that dart from country lanes and the bottlenecks that hold him up.

''It's a really strange experience on that road,'' said Mr. Porcella, 50, who drives the Taconic State Parkway 120 miles round-trip from Rhinebeck, in agrarian Dutchess County, to his job in Mount Kisco. ''It's an ever-changing show.''

When he pulls on southbound at Bulls Head Road near Rhinebeck, Mr. Porcella recognizes most cars he passes and he knows where to watch for nesting falcons.

But 20 minutes later when he stops for coffee near Poughkeepsie, feeder roads have introduced hundreds of harried motorists. Soon, two lanes expand to three. The stripe of road that has been incidental to the scenery is just another highway by the Putnam-Westchester line.

The Taconic, a 105-mile road built to establish and link state parks, has always struggled with its identity. By the time its northernmost section in Columbia County opened in 1964, the southern portions, dating to the 1930's, were being widened to serve the suburbs the road helped spawn.

Now, perhaps as at no other time, the parkway is being stretched to hold on to the past as it is retrofitted for the future.

This year, the state Transportation Department expects to authorize cell phone towers along the route. These are part of Gov. George E. Pataki's plan to coordinate wireless communication. After rejecting a contractor's initial proposal for a tower every three miles, the Transportation Department awaits a revision that may involve camouflaged towers.

Also planned are the first-ever road alterations in Dutchess and Columbia Counties, where a shoulder will be added and at least three crossroads closed. And by 2004, all 22 miles in Westchester -- save the stretch fronting Valhalla cemeteries -- will have been converted to a six-lane highway with shoulders and interchanges that will leave little evidence of the outcroppings and blind curves that were hallmarks of early parkway design.

The National Park Service has surveyed the Taconic's architectural and natural riches. The road is a designated Scenic Byway. It is being considered for the National Register of Historic Places. An advisory committee spent a year devising a management plan.

But no codes govern adjacent development. Land trusts have acquired very little land and the state controls just 200 feet of buffer on either side of the pavement, leaving it to towns in four counties to consider, or not consider, the parkway. Large homes and convenience stores increasingly poke holes in a once-uninterrupted view.

''I'm not sure how this road can go on without being destroyed,'' said Jeff Anzevino, a planner with Scenic Hudson Inc. who sits on the advisory committee. ''It's a classic death by 1,000 cuts, with cell towers, construction, the shoulders. Local officials and people who own land along the parkway need to be aware their actions will forever affect the scenic landscape.''

Following a winding course from Valhalla to Chatham, the Taconic bars commercial traffic, billboards and amenities, except for one gas station. It is a road that is in no hurry to get anywhere at a time when nearly everyone who travels it is.

''People used to go out on a Sunday afternoon and take a look at the leaves,'' said Henry Younghanse, a retired Taconic maintenance superintendent. Now, he said, with so many cars it would be too dangerous.

Many critics concede that the Transportation Department is more apt now than in the past to consider history and aesthetics along with safety. Even so, no one expects this to be F.D.R.'s Taconic again.

The Taconic is among the original ''parked driveways,'' which follow the contours of a region.

America's first, the Bronx River Parkway, was built to restore the sewage-choked river and border it with grassy parks. It opened in 1925, followed by the Hutchinson River Parkway. A 1924 law established regional park commissions to accommodate the emerging class of urban automobile owner. Mr. Roosevelt, a former state senator from Hyde Park who would be elected governor four years later, was named chairman of the Taconic Park Commission.

Mr. Roosevelt had long been sketching a ribbon road picking up at the Bronx River Parkway. He selected native stone for its bridges, designed picnic parks and persuaded landowners to donate tracts along the route, including the 6,000-acre Fahnestock State Park in Putnam County.

The parkway, first christened the Bronx River Parkway Extension, opened in sections starting in 1931, with four state parks perched on its edges.

In the absence of shoulders, the woods appeared to grow to the tire rims. In the absence of a center rail, north and southbound lanes curled together in a spiral that undulated with the whims of the landscape. Lanes were 10 feet wide, 2 feet narrower than current standards. Cars pressed tighter still each time the road passed beneath a stone bridge.

As construction progressed northward, the lanes, now 12 feet wide, separated into two fingers with a wide berm between. The periphery opened to a quilt of mountains and family farms.

Today, that section of the Taconic remains a road where natural forces guide traffic. Coyotes and turkeys gape from the sides or saunter across the road. So do deer, which contribute to five crashes daily and up to half of all accidents in some areas.

Drainage grates in the outside lane are a surprise to drivers who don't expect a periodic ''thud'' in the middle of a highway, or puddles after a rainstorm. Disabled cars prove another obstacle since there is no safety lane. It is still possible here, two hours from midtown Manhattan, to be stranded for hours late at night, owing to the dearth of passing cars.

The fact that time has had so little effect on the picture of the northern parkway is the source of considerable discord. The cell phone towers, and the $74 million plan to install shoulders with drainage from Poughkeepsie to Claverack, are as much a welcome safety improvement as a sign the state plans to convert the road to a superhighway.

Most controversial is the decision to close three intersections with small local roads. Crashes occur at those crossings at more than double the average rate for four-lane highways, the Transportation Department said. The debate on the intersections has brewed for decades, with residents of rural areas arguing that they will be inconvenienced if they are closed.

From the average 3,400 cars at Chatham, ridership rises exponentially, topping off at 90,000 cars per day at Hawthorne. Accidents from deer and weather are overshadowed by accidents from speed and volume, which are double the statewide average in northern Westchester. If past practice is any indicator, these rates should drop as the conversion from four to six lanes is done.

Also, as the Transportation Department acknowledges, much of the character has been wrung out of the southern parkway, replete with safety lanes, concrete barriers and electronic traffic signs.

But more personality is not what Claire DeBlasio wants from the road behind her Briarcliff home. She welcomed the sound barriers that separate the parkway from her backyard, and looks forward to the improved cell phone reception, the new lanes and anything else that can calm things down.

''It's bumper to bumper every morning in both directions,'' she said. ''There is always traffic. There's traffic at 3 in the morning.''